Photon-photon collision: ambiguity and duality in QCD factorization theorem

I. V. Anikin, I. O. Cherednikov, N. G. Stefanis +1

We discuss duality in ``two-photon''-like processes in the scalar ${\phi }_E^3$ model and also in the process ${\gamma }^{\ast }\gamma \to \pi \pi$ in QCD. Duality implies the equivalence between two distinct non…